Articoli di riviste: "Storm sewers"

1

Baur, R., e R. Herz. "Selective inspection planning with ageing forecast for sewer types". Water Science and Technology 46, n. 6-7 (1 settembre 2002): 389–96. http://dx.doi.org/10.2166/wst.2002.0704.

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Investments in sewer rehabilitation must be based on inspection and evaluation of sewer conditions with respect to the severity of sewer damage and to environmental risks. This paper deals with the problems of forecasting the condition of sewers in a network from a small sample of inspected sewers. Transition functions from one into the next poorer condition class, which were empirically derived from this sample, are used to forecast the condition of sewers. By the same procedure, transition functions were subsequently calibrated for sub-samples of different types of sewers. With these transition functions, the most probable date of entering a critical condition class can be forecast from sewer characteristics, such as material, period of construction, location, use for waste and/or storm water, profile, diameter and gradient. Results are shown for the estimates about the actual condition of the Dresden sewer network and its deterioration in case of doing nothing about it. A procedure is proposed for scheduling the inspection dates for sewers which have not yet been inspected and for those which have been inspected before.

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Ingole, Prof Y. R. "Design and Development of a Manual Controlled Mobile Robot for Inspection of Cracks in Storm Sewer Using Machine Learning". International Journal for Research in Applied Science and Engineering Technology 12, n. 4 (30 aprile 2024): 2895–900. http://dx.doi.org/10.22214/ijraset.2024.60538.

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Abstract: The aim of this study is to develop a "Design and Development of a Manually Controlled Mobile Robot for Inspection of Cracks in Storm Sewers using Machine Learning" with the objective of mitigating human involvement in labour-intensive and hazardous environments. Storm sewers often present challenging conditions for inspection, including toxic chemicals, fluids, and narrow or inaccessible spaces that are unsafe for human entry. These conditions necessitate the use of robots to conduct inspections and identify cracks and blockages within the sewer system. The proposed model is an in-pipe inspection robot designed specifically for storm sewers. This robot offers exceptional mobility within horizontal pipes, capable of traversing in forward direction efficiently. Equipped with advanced camera systems, the robot can detect cracks and blockages in real-time. Additionally, it provides remote access to inspection data via various interfaces such as mobile phones, smartphones, or other smart devices, allowing operators to monitor the inspection process in real-time from a safe distance.

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3

Schilperoort, Rémy, Holger Hoppe, Cornelis de Haan e Jeroen Langeveld. "Searching for storm water inflows in foul sewers using fibre-optic distributed temperature sensing". Water Science and Technology 68, n. 8 (1 ottobre 2013): 1723–30. http://dx.doi.org/10.2166/wst.2013.419.

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A major drawback of separate sewer systems is the occurrence of illicit connections: unintended sewer cross-connections that connect foul water outlets from residential or industrial premises to the storm water system and/or storm water outlets to the foul sewer system. The amount of unwanted storm water in foul sewer systems can be significant, resulting in a number of detrimental effects on the performance of the wastewater system. Efficient removal of storm water inflows into foul sewers requires knowledge of the exact locations of the inflows. This paper presents the use of distributed temperature sensing (DTS) monitoring data to localize illicit storm water inflows into foul sewer systems. Data results from two monitoring campaigns in foul sewer systems in the Netherlands and Germany are presented. For both areas a number of storm water inflow locations can be derived from the data. Storm water inflow can only be detected as long as the temperature of this inflow differs from the in-sewer temperatures prior to the event. Also, the in-sewer propagation of storm and wastewater can be monitored, enabling a detailed view on advection.

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McIlhatton, T. D., R. M. Ashley e S. J. Tait. "Improved formulations for rapid erosion of diverse solids in combined sewers". Water Science and Technology 52, n. 5 (1 settembre 2005): 143–50. http://dx.doi.org/10.2166/wst.2005.0128.

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For more than a decade, research carried out in Scotland has investigated the movement of sediment in sewers and the associated pollutant release. Pollution by discharges from combined sewer overflows can adversely affect watercourses, particularly those in urban areas. Solids and dissolved contaminants, many derived from in-sewer deposits during a storm event, can be especially significant. This phenomenon can occur during events known as ‘foul flushes’. In combined sewers these typically occur in the initial period of storm flows, when the concentration of suspended sediments and other pollutants is significantly higher than at other times. It has become apparent that much of the suspended load originates from solids eroded from the bed. The ‘near bed solids’ which are re-entrained into the flow, together with solids eroded from the bulk bed, account for large changes in the suspended sediment concentration under time varying flow conditions. This paper describes some of the methods employed to investigate the solids eroding in combined sewers during peak flow events. The work examined the potential for sediment re-suspension under high flow conditions both in the laboratory and in the field.

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5

Arthur, S., e R. M. Ashley. "The influence of near bed solids transport on first foul flush in combined sewers". Water Science and Technology 37, n. 1 (1 gennaio 1998): 131–38. http://dx.doi.org/10.2166/wst.1998.0032.

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The problems associated with deposited sediments in sewers, and their transport through sewer systems have been the subject of detailed fieldwork programmes in the UK, and elsewhere in Europe. Existing laboratory, and some field based research exercises have focused on the relatively small, discrete particles. It is clear, however, that combined sewer systems have inputs which comprise of a significant proportion of large organic solids (faecal and food wastes), as well as the finer range of particle sizes. The increased concern regarding CSO spills into the environment has fuelled the recent development of sewer flow quality models, such as HYDROWORKS QM and MOUSETRAP, some of which make no attempt to represent the transport of these larger organic particles. Herein, the results of a collaborative research programme undertaken between three UK universities and a water authority are discussed. Transport at the bed in sewers, as “near bed solids”, is defined. Based on a comprehensive data collection program undertaken in the Dundee combined sewerage system, a method is presented which may be used to estimate the rate of sediment transport near the bed in sewers. The influence that solids in transport near the bed have on first foul flush in combined sewers is discussed. A methodology is proposed which may be used to estimate the extent to which sediment in transport near the bed in sewers contributes to first foul flush phenomena, by describing the movement of a storm wave along a conceptual sewer length.

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Xu, Zuxin, Jun Wu, Huaizheng Li, Zhenghua Liu, Keli Chen, Hao Chen e Lijun Xiong. "Different erosion characteristics of sediment deposits in combined and storm sewers". Water Science and Technology 75, n. 8 (8 febbraio 2017): 1922–31. http://dx.doi.org/10.2166/wst.2017.076.

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To investigate the different erosion patterns of sediments in combined and storm sewers, sediments from three separate sewer systems and two combined sewer systems in urban Shanghai were collected for the flushing experiments. These experiments were conducted with different consolidation periods and shear velocities. As the consolidation period increases, dissolved oxygen exhibits a positive effect on the microbial transformations of organic substrates. Potential structural changes and separations of the surface and bottom layers of sediments are observed. The results also reveal that the organic matter, particle size and moisture have different effects on the erosion resistance of sediments. Furthermore, illicit connections behaved as an important factor affecting the viscosity and static friction force of particles, which directly alter the erosion resistance of sewer sediments.

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7

Ruan, Mingchaun, e Jan B. M. Wiggers. "Application of time-series analysis to urban storm drainage". Water Science and Technology 36, n. 5 (1 settembre 1997): 125–31. http://dx.doi.org/10.2166/wst.1997.0180.

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In urban storm drainage, deterministic models, such as SWMM, HydroWorks and MOUSE are commonly used. However, comprehensive research programmes, including field surveys, have indicated that most processes related to urban storm drainage have stochastic characteristic, like the occurrence of rainfall events, the processes of rainfall-runoff and flow routing in sewer networks3etc.. Particularly, sediments found in sewers either in suspension or in deposition, cannot be considered as having a unique entity. Inhomogeneity and randomness are just the nature of sewer sediment behaviour. Most data required for urban storm drainage are time-series data, such as rainfall intensity, water level measured in an outfall, CSO discharge and pollutant load etc.. Consequently, time-series analysis should be an alternative for predicting some relationships of urban storm drainage, such as (net) rainfall-CSO discharge, rainfall-water level and CSO discharge-pollutant load.

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8

Coghlan, Brian P., Richard M. Ashley e George M. Smith. "Empirical equations for solids transport in combined sewers". Water Science and Technology 33, n. 9 (1 aprile 1996): 77–84. http://dx.doi.org/10.2166/wst.1996.0181.

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An investigation of the transport of solids in combined sewers during both dry weather flow (DWF) periods and storms is described. The study was based on data obtained from a number of sites in the combined sewer system of Dundee, Scotland. The relationship between hydraulic conditions in a combined sewer and the transport of solids in suspension was examined. The aim was to arrive at a methodology by which an appropriate model could be selected or developed which would predict solids transport rates given information on hydraulic conditions. It was found that for individual sites, site-specific regression equations could be developed separately for dry weather and storm conditions. A non-site-specific regression equation was also developed, which was found to be preferable to the site specific equations, in terms of accuracy and ease of use. More important, however, were the fundamental procedures (ie the methodology) developed by which the model type was in each case selected and subsequently developed.

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9

Vollertsen, J., e T. Hvitved-Jacobsen. "Exfiltration from gravity sewers: a pilot scale study". Water Science and Technology 47, n. 4 (1 febbraio 2003): 69–76. http://dx.doi.org/10.2166/wst.2003.0223.

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Pilot-scale experiments were conducted on exfiltration of wastewater from gravity sewers. The effect of storm events, flushing of pipes and alternating infiltration/exfiltration were simulated. Exfiltration through different types of sewer leaks and into different soils were studied. It was found that the exfiltration rate became constant after some days of exfiltration. It stayed constant for the duration of the experiments, which typically spanned over some weeks. The exfiltration was governed by the development of a clogging zone at the sewer leak and could be characterized by a leakage factor. The leakage factor may then be used to estimate the risk of groundwater pollution from a sewer network.

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10

Pan, Gang, Bao Wang, Shuai Guo, Wenming Zhang e Stephen Edwini-Bonsu. "Statistical analysis of sewer odour based on 10-year complaint data". Water Science and Technology 81, n. 6 (15 marzo 2020): 1221–30. http://dx.doi.org/10.2166/wst.2020.217.

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Abstract The City of Edmonton has been suffering from sewer odour problem for many years. Ten years of odour complaints data from 2008 to 2017 were statistically analyzed to identify major factors that relate to the odour problem. Spatial and temporal distributions of odour complaints in the city were first presented. Then relationships between the complaints and physical attributes of the sewer systems were analyzed by introducing a parameter of risk index. It was found that the snowmelt and storm events could possibly reduce odour complaints. Old sewer pipes and large drop structures are statistically more linked and thus significantly contribute to the complaints. The risk index relationship for three pipe materials is clay pipe > concrete pipe > PVC pipe. Combined sewers are more problematic in terms of odour complaints than sanitary sewers. And no clear correlation has been found between the changes of sewer pipe slope or angle and the complaints.

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11

Langeveld, J. G., C. de Haan, M. Klootwijk e R. P. S. Schilperoort. "Monitoring the performance of a storm water separating manifold with distributed temperature sensing". Water Science and Technology 66, n. 1 (1 luglio 2012): 145–50. http://dx.doi.org/10.2166/wst.2012.152.

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Storm water separating manifolds in house connections have been introduced as a cost effective solution to disconnect impervious areas from combined sewers. Such manifolds have been applied by the municipality of Breda, the Netherlands. In order to investigate the performance of the manifolds, a monitoring technique (distributed temperature sensing or DTS) using fiber optic cables has been applied in the sewer system of Breda. This paper describes the application of DTS as a research tool in sewer systems. DTS proves to be a powerful tool to monitor the performance of (parts of) a sewer system in time and space. The research project showed that DTS is capable of monitoring the performance of house connections and identifying locations of inflow of both sewage and storm runoff. The research results show that the performance of storm water separating manifolds varies over time, thus making them unreliable.

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12

Li, James, e Alex McCorquodale. "Modeling Mixed Flow in Storm Sewers". Journal of Hydraulic Engineering 125, n. 11 (novembre 1999): 1170–80. http://dx.doi.org/10.1061/(asce)0733-9429(1999)125:11(1170).

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13

Zhou, F., F. Hicks e P. Steffler. "Analysis of effects of air pocket on hydraulic failure of urban drainage infrastructure". Canadian Journal of Civil Engineering 31, n. 1 (1 gennaio 2004): 86–94. http://dx.doi.org/10.1139/l03-077.

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The effects of trapped air on flow oscillations and pressure surges in a model trunk sewer–manhole system subject to rapid filling are investigated. The study reveals the detrimental impacts of entrapped air during severe storm events under which pipelines are likely overloaded. The results of the investigation indicated huge peak pressures and severe pressure oscillations inside the system.Key words: trapped air, flow transient, rapid filling, sewers.

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14

Marsalek, J., T. O. Barnwell, W. Geiger, M. Grottker, W. C. Huber, A. J. Saul, W. Schilling e H. C. Torno. "Urban Drainage Systems: Design and Operation". Water Science and Technology 27, n. 12 (1 giugno 1993): 31–70. http://dx.doi.org/10.2166/wst.1993.0291.

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Design and operation of urban drainage systems are addressed in the context of the urban water system comprising drainage, sewage treatment plants and receiving waters. The planning and design of storm sewers are reviewed with reference to planning objectives, design objectives, flows and pollutant loads, sewer system structures and urban runoff control and treatment. The discussion of combined sewers focuses on hydraulic design of combined sewer systems, including combined sewer overflow (CSO) structures, and the use of CSO structures and storage in control of CSOs. The section on operation of sewer systems focuses on real time control, its feasibility, planning, design, operation and applications. Sewer system planning and design are generally conducted using computer modelling tools and procedures which are reviewed in the last section. A brief listing of selected models focuses on internationally used models. Finally, it was concluded that further improvements in environmental and ecological protection of urban waters is feasible only by consideration of urban drainage systems in conjunctions with sewage treatment and water quality in the receiving waters.

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15

Nalluri, Chandramouli, e Aminuddin Ab Ghani. "Design options for self-cleansing storm sewers". Water Science and Technology 33, n. 9 (1 aprile 1996): 215–20. http://dx.doi.org/10.2166/wst.1996.0214.

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A list of available codes of practice for self-cleansing sewers is presented and a review of appraisals of minimum velocity criterion is summarised. Comparisons of newly developed “minimum velocity” criteria and “minimum shear stress” criterion are presented. Some design charts are also given. These charts are applicable to non-cohesive sediments (typically storm sewers). It appears that sediment size and concentration need to be taken into account, and that a limited depth of sediment bed is recommended for large pipes (diameters > 1000 mm) to maximise their transport capacity.

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Lee, Jimin, Jinsun Kim, Jong Mun Lee, Hee Seon Jang, Minji Park, Joong Hyuk Min e Eun Hye Na. "Analyzing the Impacts of Sewer Type and Spatial Distribution of LID Facilities on Urban Runoff and Non-Point Source Pollution Using the Storm Water Management Model (SWMM)". Water 14, n. 18 (6 settembre 2022): 2776. http://dx.doi.org/10.3390/w14182776.

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The negative changes in the hydrological cycle are increasing due to climate change and urbanization, resulting in deterioration of water quality and environmental issues. Although Low-Impact Development (LID) techniques studies have been conducted to solve this problem, the spatial distribution of LID facilities and sewer types has received less attention. In this study, it is proposed to analyze the effects of sewer type, the spatial distribution of LID facilities, and LID type on runoff and water quality using the Storm Water Management Model and to identify effective ways of improving the hydrological cycle and Non-Point Source (NPS) pollution associated with urbanization. As a result of the runoff reduction analysis, 68% of the rainfall was discharged at the outlet for separate sewers, 79% for combined sewers without storage tank, and 49% for combined sewers with storage tank. The LID scenario results showed the distributed LID application method has higher reduction efficiency of runoff and NPS pollution than the intensive application method. Moreover, intensive application of LID in downstream areas resulted in higher runoff reduction efficiency than the application of LID in upstream areas. It will be used not only in the hydrological cycle plan but also in NPS pollution management.

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Delleur, J. W., e Y. Gyasi-Agyei. "Prediction of Suspended Solids in Urban Sewers by Transfer Function Model". Water Science and Technology 29, n. 1-2 (1 gennaio 1994): 171–79. http://dx.doi.org/10.2166/wst.1994.0663.

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There is increasing concern about the sediments transported in urban storm sewers. Progress has been made on the measurement of suspended solids, and telemetry systems have been installed that permit remote access to flow, temperature and suspended solids concentration data. Using observations obtained in the main trunk sewer in Brussels, Belgium, a transfer function model for the prediction of suspended load concentration from temperature and discharge measurements was developed. This model is based on the transfer function methodology developed by Box and Jenkins. It is shown that the transfer function model correctly tracks the suspended solids observations and makes reasonable forecasts. It provides a valid alternative for the determination of suspended solids in urban sewers from discharge and water temperature observations which are more easily measurable on line than suspended solids.

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18

Mcllhatton, T. D., R. Sakrabani, R. M. Ashley e R. Burrows. "Erosion mechanisms in combined sewers and the potential for pollutant release to receiving waters and water treatment plants". Water Science and Technology 45, n. 3 (1 febbraio 2002): 61–69. http://dx.doi.org/10.2166/wst.2002.0055.

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The problems associated with solids in sewerage systems result in common difficulties such as blockages and flooding and the subsequent maintenance requirements have been well documented. Concerns regarding pollutant release have also been demonstrated, with the contribution from in-sewer solids to the quality of the flow during a storm event being especially significant. These events known as “foul flushes” in combined sewers typically occur in the initial period of storm flows, when the concentration of suspended sediments and other pollutants are significantly higher than at other times. Traditionally impacts from these events have been related to the suspended solids phase of the flow passing through a CSO structure. It is now apparent that much of the suspended load originates from solids eroded from the bed. The “near bed solids” which are re-entrained into the flow, together with solids eroded from the bulk bed, account for large changes in the suspended sediment concentration under time varying flow conditions. The influence of these eroded solids and their potential impact on receiving waters and treatment plants will be reviewed using data obtained from field studies carried out in the main Dundee interceptor sewer in Scotland. This paper describes some of the methods employed to investigate the characteristics of the pollutants associated with solids erosion in combined sewers.

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Crabtree, R., H. Garsdal, R. Gent, O. Mark e J. Dórge. "MOUSETRAP — A DETERMINISTIC SEWER FLOW QUALITY MODEL". Water Science and Technology 30, n. 1 (1 luglio 1994): 107–15. http://dx.doi.org/10.2166/wst.1994.0011.

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Recent research into the behaviour of sediments and associated pollutants in sewers has formed the foundation for a dynamic pollutograph-based sewer flow quality simulation model called MOUSETRAP. This is a new component to the MOUSE sewer system hydraulic modelling package. MOUSETRAP has been developed by an international consortium of sewer model developers and users to predict short term variations in sewer flow quality and sediment transport in response to storm events. MOUSETRAP is composed of a series of modules to represent: the quality of surface run off; sediment and pollutant transport, erosion and deposition within pipes; and the biological and chemical processes within the sewer system. By representing the current understanding of real sewer sediments, this new tool gives the user the capability to simulate storm event pollutographs incorporating first foul flush phenomena. The paper describes the basis of the new MOUSETRAP modules. Results of initial theoretical testing and pilot study applications are presented to illustrate the model's capabilities and potential for use in the management of urban wastewater discharges.

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Tang, Yangbo, David Z. Zhu e Bert van Duin. "Erosion on Cohesive Deposition in Storm Sewers". Journal of Environmental Engineering 146, n. 12 (dicembre 2020): 04020136. http://dx.doi.org/10.1061/(asce)ee.1943-7870.0001824.

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21

Nienhuis, Jaap, Cornelis de Haan, Jeroen Langeveld, Martijn Klootwijk e François Clemens. "Assessment of detection limits of fiber-optic distributed temperature sensing for detection of illicit connections". Water Science and Technology 67, n. 12 (1 giugno 2013): 2712–18. http://dx.doi.org/10.2166/wst.2013.176.

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Distributed temperature sensing (DTS) with fiber-optic cables is a powerful tool to detect illicit connections in storm sewer systems. High-frequency temperature measurements along the in-sewer cable create a detailed representation of temperature anomalies due to illicit discharges. The detection limits of the monitoring equipment itself are well-known, but there is little information available on detection limits for the discovery of illicit connections, as in mixing of sewers, and attenuation also plays an important role. This paper describes the results of full-scale experiments aiming to quantify the detection limits for illicit connections under various sewer conditions. Based on the results, a new monitoring set-up for (partially) filled sewer conduits has been proposed.

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Villeneuve, Jean-Pierre, Eric Gaume e France Michaud. "Efficiency evaluation of an installed swirl separator". Canadian Journal of Civil Engineering 21, n. 6 (1 dicembre 1994): 924–30. http://dx.doi.org/10.1139/l94-098.

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Municipalities try to limit overflow of their sewer systems by various technologies such as storage in basins and transfer of the water after the storm to a treatment facility, storage and decantation, on-line treatment of overflows, or by alternative technologies like porous roadways or runoff infiltration. The swirl separator, proposed by the American Public Work Association, is an attractive device, because it requires little supervision and maintenance. However, only few results exist about its efficiency for treating combined sewer overflow. The purpose of the present field study was to determine the performance of an existing device (the Québec swirl regulator). The results, presented herein, show that up to 25% of the suspended solids transported during storms can be eliminated, but most of the liquid–solid separation seems to take place in the upstream collecting pipe. Key words: combined sewers, overflows, water treatment, suspended sediments.

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Li, James, Robert Orland e Tom Hogenbirk. "Environmental road and lot drainage designs: alternatives to the curb-gutter-sewer system". Canadian Journal of Civil Engineering 25, n. 1 (1 gennaio 1998): 26–39. http://dx.doi.org/10.1139/l97-044.

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Traditionally, road and lot drainage systems have been designed to convey storm runoff away as quickly as possible to reduce localized ponding. This drainage concept, using curb-gutter-sewer systems, has led to downstream flooding, erosion, water-quality degradation, reduced groundwater recharge and stream baseflow, and aquatic habitat destruction. This paper examines the pros and cons of curb-gutter-sewer systems and qualitatively compares various forms of open ditch - swale drainage alternatives with the conventional curb-gutter-sewer drainage system. These open ditch - swale drainage alternatives not only provide drainage functions but also promote infiltration, trap sediments, and reduce flow velocity along the drainage path. Thus, they can reduce erosion, enhance runoff quality, and increase groundwater recharge. However, they usually require a wider right-of-way than the conventional curb-gutter-sewer systems and may not be suitable for sites with steep topography or erosive soils. For sites that are suitable for the application of these alternative drainage systems, their environment functions make them more attractive than the conventional curb-gutter-sewer system.Key words: drainage systems, storm water, curbs, gutters, sewers, ditches, swales.

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Lee, Jong Mun, Minji Park, Joong-Hyuk Min, Jinsun Kim, Jimin Lee, Heeseon Jang e Eun Hye Na. "Evaluation of SWMM-LID Modeling Applicability Considering Regional Characteristics for Optimal Management of Non-Point Pollutant Sources". Sustainability 14, n. 21 (7 novembre 2022): 14662. http://dx.doi.org/10.3390/su142114662.

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Urbanization and climate change have deteriorated the runoff water circulation and quality in urban areas worldwide. Consequently, low-impact development (LID) and green infrastructure (GI) techniques have been applied to manage impermeable land and non-point source pollutants. Herein, the impacts of urban characteristics, sewer system type, and precipitation intensity on surface runoff were analyzed using the Storm Water Management Model (SWMM) to derive an effective water circulation strategy for urban and complex areas through the optimal allocation of LID/GI strategies. The runoff rates were estimated to be 77.9%, 37.8%, and 61.7% for urban areas with separated and combined sewer systems and complex areas with combined sewer systems, respectively. During low rainfall, runoff was intercepted in areas with combined sewer systems, and runoff and pollutant load were lower than that in areas with separated sewer system. In contrast, wastewater was diluted during heavy rainfall; however, the total pollutant load was higher than in separated areas. The analysis of scenarios according to the regional distribution of each LID type resulted in high efficiency when combined sewers were applied during the distributed placement of catchment areas. Additionally, LID infrastructure was applied in areas with separated sewers when the placement was concentrated at the end of the basin.

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Raza, Usman, e Abdul Salam. "Wireless Underground Communications in Sewer and Stormwater Overflow Monitoring: Radio Waves through Soil and Asphalt Medium". Information 11, n. 2 (11 febbraio 2020): 98. http://dx.doi.org/10.3390/info11020098.

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Storm drains and sanitary sewers are prone to backups and overflows due to extra amount wastewater entering the pipes. To prevent that, it is imperative to efficiently monitor the urban underground infrastructure. The combination of sensors system and wireless underground communication system can be used to realize urban underground IoT applications, e.g., storm water and wastewater overflow monitoring systems. The aim of this article is to establish a feasibility of the use of wireless underground communications techniques, and wave propagation through the subsurface soil and asphalt layers, in an underground pavement system for storm water and sewer overflow monitoring application. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. The dielectric properties of asphalt, sub-grade aggregates, and soil are considered in the path loss analysis for the path loss prediction in an underground sewer overflow and wastewater monitoring system design. It has been shown that underground transmitter was able to communicate through thick asphalt (10 cm) and soil layers (20 cm) for a long range of up to 4 km.

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Mustapha, Tajudeen Dele, e Patric Kelechi Nwaokwa. "An Evaluation of the Central Sewage System (CSS) Problem in Abuja". Shodh Sari-An International Multidisciplinary Journal 02, n. 04 (5 ottobre 2023): 248–72. http://dx.doi.org/10.59231/sari7638.

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The Abuja Central Sewage System (CSS) is an essential facility in the capital city. The CSS efficiency must not be compromised due to the enormous effects of sewage malfunction on the environment and its inhabitants. This research aims to study the problem of the Abuja Central Sewage System (CSS) problem, identify related issues, and provide alternative solutions. To achieve this goal, field research was undertaken in Phase 1 of the Federal Capital City (Abuja), with a questionnaire randomly administered to two hundred respondents in five (5) districts. The survey questionnaire was given to only building tenants acquainted with building services, particularly liquid waste disposal, such as the underground sewage system. The data were evaluated with descriptive statistical methods like percentages, means, and standard deviation. It was established that sanitary sewers overflowed from manholes onto streets and eventually into storm drains. The waste is not treated before being deposited into surrounding watercourses. It was also revealed that manholes release foul odors from sanitary sewers. These hazards pollute the environment and endanger public health. The study concluded that the Federal Capital City’s sanitary sewers were somewhat successful in collecting and transporting sewage. The study suggested improving service delivery efficiency through routine training in collection system operations, maintenance, and supervision, as well as integrating cutting-edge technologies like closed-circuit television into the sewer system’s maintenance program to increase the sewer efficiency system.

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Tang, Yangbo, David Z. Zhu, N. Rajaratnam e Bert van Duin. "Experimental study of hydraulics and sediment capture efficiency in catchbasins". Water Science and Technology 74, n. 11 (22 settembre 2016): 2717–26. http://dx.doi.org/10.2166/wst.2016.448.

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Catchbasins (also known as gully pot in the UK and Australia) are used to receive surface runoff and drain the stormwater into storm sewers. The recent interest in catchbasins is to improve their effectiveness in removing sediments in stormwater. An experimental study was conducted to examine the hydraulic features and sediment capture efficiency in catchbasins, with and without a bottom sump. A sump basin is found to increase the sediment capture efficiency significantly. The effect of inlet control devices, which are commonly used to control the amount of flow into the downstream storm sewer system, is also studied. These devices will increase the water depth in the catchbasin and increase the sediment capture efficiency. Equations are developed for predicting the sediment capture efficiency in catchbasins.

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28

Volschan, Isaac. "The challenge of dry-weather sewage intakes as a sustainable strategy to develop urban sanitation in the tropics". Water Practice and Technology 15, n. 1 (23 dicembre 2019): 38–47. http://dx.doi.org/10.2166/wpt.2019.084.

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Abstract Informal housing, and operational and management deficiencies, influence sewerage system performance in Brazil. Inadequate sewage volumes in storm sewers lead to fecal contamination and affect recreational water environments. As overflow structures, dry-weather sewage intakes (DWSIs) are used to intercept and transfer sewage from storm- to sewage- sewers. For cities without public services, the DWSI strategy has been suggested as an option to enable easier and more rapid responses in terms of sewage pollution control. The strategy may also lead to gradual construction of a separate sewerage system in a two-step plan: initially, based on the construction of DWSIs and wastewater treatment plants, and then, on the construction of separate sewers. The paper is a discussion of the main technical challenges in sustainability of the DWSI strategy, and includes a case study of slum and other informal housing areas in Rio de Janeiro.

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29

Seco, I., M. Gómez Valentín, A. Schellart e S. Tait. "Erosion resistance and behaviour of highly organic in-sewer sediment". Water Science and Technology 69, n. 3 (26 novembre 2013): 672–79. http://dx.doi.org/10.2166/wst.2013.761.

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Reliable prediction of time-varying pollutant loads in combined sewer systems during storm periods can aid better management of the release of pollution into natural environments as well as enhancing storage tank design. Better understanding of the behaviour of sewer sediments is crucial for the development of models that adequately describe the transport of in-sewer solids and accurately predict the changes in pollutant concentration within combined sewers during storm events. This paper reports on the results of a test programme to examine the erosion of highly organic sewer sediment under the application of time-varying shear stress. The tests were carried out with and without supplying oxygen, and varying simulated dry-weather periods. The aim was to investigate the behaviour of real in-sewer sediment with a high organic content (around 80%) in an attempt to improve prediction of the transport rates under the particular Mediterranean conditions of long dry-period/build-up and intense rainfall/wash-off, and understand how this environment affects the erosional resistance and subsequent sediment release. Results have been compared with previous work on lower organic content sewer sediments and artificial organic sediment.

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30

Panasiuk, Oleksandr, Annelie Hedström, Jeroen Langeveld, Cornelis de Haan, Erik Liefting, Remy Schilperoort e Maria Viklander. "Using Distributed Temperature Sensing (DTS) for Locating and Characterising Infiltration and Inflow into Foul Sewers before, during and after Snowmelt Period". Water 11, n. 8 (24 luglio 2019): 1529. http://dx.doi.org/10.3390/w11081529.

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Abstract (sommario):

Infiltration and inflow (I/I) into sewers cause negative effects on the sewer system, wastewater treatment plant and environment. Identifying the causes and locating the inflows is necessary in order to address the I/I problem. This paper focuses on using distributed temperature sensing (DTS) for identifying, locating and characterising I/I into a sewer system during the end of winter–beginning of summer transition period under dry and wet weather conditions. During snowmelt, several locations with I/I were identified, while these locations did not show I/I during storm events after the snowmelt. In addition, during a very heavy storm after the snowmelt period, I/I was found at other locations. Therefore, DTS was demonstrated to be effective in identifying the type of I/I and in locating I/I. Finally, I/I monitoring campaigns in cold climates should take into account the variety of pathways of I/I during snowmelt and during rainfall.

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31

Leo, Steve. "Strategic Asset Management Planning for Separate Storm Sewers". Proceedings of the Water Environment Federation 2010, n. 1 (1 gennaio 2010): 176–200. http://dx.doi.org/10.2175/193864710798286984.

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32

Fuamba, Musandji. "Contribution on transient flow modelling in storm sewers". Journal of Hydraulic Research 40, n. 6 (novembre 2002): 685–93. http://dx.doi.org/10.1080/00221680209499915.

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33

Akan, A. Osman. "Risk Model for Storm Sewers with Submerged Outlets". Journal of Environmental Engineering 113, n. 6 (dicembre 1987): 1376–84. http://dx.doi.org/10.1061/(asce)0733-9372(1987)113:6(1376).

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34

Kanso, A., G. Chebbo e B. Tassin. "Stormwater quality modelling in combined sewers: calibration and uncertainty analysis". Water Science and Technology 52, n. 3 (1 agosto 2005): 63–71. http://dx.doi.org/10.2166/wst.2005.0062.

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Abstract (sommario):

Estimating the level of uncertainty in urban stormwater quality models is vital for their utilization. This paper presents the results of application of a Monte Carlo Markov Chain method based on the Bayesian theory for the calibration and uncertainty analysis of a storm water quality model commonly used in available software. The tested model uses a hydrologic/hydrodynamic scheme to estimate the accumulation, the erosion and the transport of pollutants on surfaces and in sewers. It was calibrated for four different initial conditions of in-sewer deposits. Calibration results showed large variability in the model's responses in function of the initial conditions. They demonstrated that the model's predictive capacity is very low.

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35

Hussein, A. O., Shamsuddin Shahid, K. N. Basim e Shreeshivadasan Chelliapan. "Modelling Stormwater Quality of an Arid Urban Catchment". Applied Mechanics and Materials 735 (febbraio 2015): 215–19. http://dx.doi.org/10.4028/www.scientific.net/amm.735.215.

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Abstract (sommario):

Understanding quality of stormwater is important for effective urban rainwater treatment planning and management. In this study, the quality of stormwater runoff from an arid urban residential catchment located in the Karbala city of Iraq, draining through stormwater sewers was investigated. The Storm Water Management Model (SWMM) was used to estimate the concentrations of pollutants in stormwater and wastewater in the sewer networks. The results showed that the concentrations of the Biological Oxygen Demand (BOD5) and Total Suspended Solids (TSS) increased significantly after rain in the study area. The increase of TSS was very high compared to the BOD5. It is expected that the long-term simulations of stormwater pollution loading will help to compare the benefits of different scenarios of the sewage treatment plan for the reduction of the pollution in the storm discharge area.

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36

Gong, N., X. Ding, T. Denoeux, J. L. Bertrand-Krajewski e M. Clément. "Stormnet: a connectionist model for dynamic management of wastewater treatment plants during storm events". Water Science and Technology 33, n. 1 (1 gennaio 1996): 247–56. http://dx.doi.org/10.2166/wst.1996.0024.

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Abstract (sommario):

Models for solid transport in sewers during storm events are increasingly used. An important application of these models is the management of treatment plants during storm events so as to improve the quality of receiving waters. However, a major difficulty that prevents more general use of these tools is their calibration, which requires field data, accurate information about catchments and sewers, and a specific methodology. For that reason, a connectionist model called STORMNET has been designed to reproduce and replace usual conceptual and deterministic models. This model requires fewer data, can be automatically calibrated, and is comparatively simple. It is composed of two recurrent neural networks for the simulation of hydrographs and pollutographs of suspended solids, respectively. In this paper, we present an updated version of STORMNET designed for optimal management of wastewater treatment plants during storm events. This model has been validated using both model and real data. The results show the efficiency of STORMNET as a computational tool for simulating stormwater pollution.

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37

Stirrup, M., Z. Vitasovic e E. Strand. "Real-Time Control of Combined Sewer Overflows in Hamilton-Wentworth Region". Water Quality Research Journal 32, n. 1 (1 febbraio 1997): 155–68. http://dx.doi.org/10.2166/wqrj.1997.011.

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Abstract (sommario):

Abstract The Regional Municipality of Hamilton-Wentworth operates and maintains a large combined sewer system in the Great Lakes basin. During dry weather and small storm events, two large interceptor sewers convey all sanitary and storm flows to the Woodward Avenue wastewater treatment plant. Larger rainfall events, specifically high intensity summer thunderstorms, generate flows which exceed the design capacity of the sanitary interceptors and result in combined sewer overflows to Hamilton Harbour and Cootes Paradise, which ultimately discharge to Lake Ontario. The Region is implementing a comprehensive program for reducing the pollution caused by these overflows. This program includes the construction of several off-line detention storage facilities and the implementation of a real-time control system for combined sewer overflow reduction. Real-time control will enable maximum utilization of the storage available within the combined sewer network and help reduce the frequency and volume of combined sewer overflows. New hydrologic and hydraulic simulation models have been specially developed for this project to help identify, test and implement optimal real-time control strategies. This paper discusses some of the more important aspects related to the design and implementation of the Region’s real-time control system, and focuses mainly on the development of these hydrologic and hydraulic simulation models.

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38

Schaarup-Jensen, Kjeld, Thorkild Hvitved-Jacobsen, Bent Jütte, Bjarne Nielsen e Tage Pedersen. "A Danish sewer research and monitoring station". Water Science and Technology 37, n. 1 (1 gennaio 1998): 197–204. http://dx.doi.org/10.2166/wst.1998.0048.

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Abstract (sommario):

A research and monitoring station has been established as a part of the intercepting sewer from Frejlev, a small town of 2000 inhabitants 7 km Southwest of Aalborg, Denmark. The purpose is to perform continuous high quality time series of flow as well as waste water and runoff water characteristics. Based on these future time series, research will be carried out in order to establish knowledge on dry weather characteristics, and rainfall-runoff relationships including the variability of relevant storm water pollutants. Furthermore, the measurements can form the basis of a better understanding of transport and transformation of pollutants in combined sewers including suspended and bed load characteristics, sedimentation and resuspension.

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39

Mailhot, Alain, Sophie Duchesne, Emmanuelle Musso e Jean-Pierre Villeneuve. "Modélisation de l'évolution de l'état structural des réseaux d'égout : application à une municipalité du Québec". Canadian Journal of Civil Engineering 27, n. 1 (15 febbraio 2000): 65–72. http://dx.doi.org/10.1139/l99-054.

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Abstract (sommario):

Many sanitary and storm sewer networks are old and deteriorating rapidly. Water and sanitation managers are becoming more and more aware of the negative impact of poorly maintained sewer networks, especially since they are asked to comply with stricter environmental standards under already challenging budget constraints. The best way to improve the structural condition of a sewer network is to replace failed pipe sections. Planning replacement works necessitates knowledge of the present structural state of the network and of the evolution of this state in the near future. Towards this goal, a predictive modelling strategy was developed for the structural state of a sewer network. A case study in a Quebec municipality is presented to illustrate how the modelling strategy developed can be used to simulate the evolution, over the next 20 years, of the length of a sewer network in poor state, and to assess the impact of different replacement strategies on the global state of the network. Key words: urban infrastructures, sewers, structural state, modelling.

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40

Knolmar, Marcell, Tamas Karches e Nikolett Balogh. "COMPUTATIONAL FLUID DYNAMICS DISCRETE PHASE MODELLING IN STORM SEWERS". Environmental Engineering and Management Journal 19, n. 4 (2020): 557–63. http://dx.doi.org/10.30638/eemj.2020.053.

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41

Almedeij, Jaber, e Nora Almohsen. "Remarks on Camp’s Criterion for Self-Cleansing Storm Sewers". Journal of Irrigation and Drainage Engineering 136, n. 2 (febbraio 2010): 145–48. http://dx.doi.org/10.1061/(asce)ir.1943-4774.0000129.

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42

Kichev, Dmitrij, Anna Matveeva e Mihail Kichev. "On the Issue of the Ecological State of Storm Wastewater in an Urbanized Territory". Natural Systems and Resources, n. 4 (marzo 2021): 5–11. http://dx.doi.org/10.15688/nsr.jvolsu.2020.4.1.

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Abstract (sommario):

The article raises the issue of the ecological state of storm wastewater, their technical condition. The issues of assessing the functioning of storm sewers are included in the list of municipal environmental control, which is carried out by the executive authorities in the field of ecology and nature management. The research paper outlines the key problems associated with underfunding of the current work to ensure the efficient operation of storm water. The main categories in the system “treatment facilities – storm drains – collectors” are considered. The traditional stormwater runoff system involves the diversion of surface runoff through open water bodies (e.g. river systems). The main environmental indicators to be achieved during the construction and commissioning of a complex of sewage storm treatment facilities have been analyzed. The analysis of the design indicators showed that a total of 18.9 million m3 of storm water, rainwater runoff and drainage waters are subject to treatment. The measures for the installation of sewage treatment plants, storm sewers will prevent the river Volga from entering of more than 22 thousand tons of suspended solids, including heavy metals and 1.2 thousand tons of oil products. According to the project documentation, the construction of more than 50 facilities will allow upgrading the stormwater drainage system of the city of Volgograd within the framework of the National Project “Ecology”. The conclusions reflected in the article reveal the main reasons for the current situation: inconsistency of repair and restoration work to replace parts, assemblies; insufficient amount of technical re-equipment; inconsistency of the chemical composition of wastewater with the established regulatory environmental indicators; insufficient municipal control of the services responsible for this object; insufficient financial support.

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43

Staufer, P., e J. Pinnekamp. "In situ measurements of shear stresses of a flushing wave in a circular sewer using ultrasound". Water Science and Technology 57, n. 9 (1 maggio 2008): 1363–68. http://dx.doi.org/10.2166/wst.2008.300.

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Abstract (sommario):

Deposits build up in sewer networks during both spells of dry weather and in connection with storm water events. In order to reduce the negative effects of deposit on the environment, different cleaning technologies and strategies are applied to remove the deposits. Jet cleaning represents the most widely used method to clean sewers. Another alternative cleaning procedure is flushing. On account of new developments in measurement and control panels, the flushing method is becoming more important. Therefore, in the last few years a number of new flushing devices have been constructed for application in basins, main sewers and initial reaches. Today, automatic flushing gates are able to accomplish cleaning procedures under economical and ecological conditions. The properties of flushing waves for cleaning sewers have been determined by several mathematical-numerical studies. These various investigations use altering numerical schemes, are based on different sets of physical equations and take one- or more dimensional aspects into account. Considering that bottom shear stress is the key value to evaluate the beginning of motion of any deposit, one may use this value that has to be determined by measurements. This paper deals with shear stresses caused by flushing waves which have been measured by an ultrasonic device that can determine the velocity in different depths of flow. Thus, it is possible, within certain limits, to calculate bottom shear stresses based on the log-wall law. Further discussion will deal with the requirements of measurements, its uncertainty and aspects in respect to the application of simulation of flushing waves.

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44

Julínek, Tomáš, e Jaromír Říha. "Assessing stream water quality influenced by storm overflows from sewers". Pollack Periodica 12, n. 2 (agosto 2017): 117–28. http://dx.doi.org/10.1556/606.2017.12.2.10.

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45

Gong, Ning, Thierry Denoeux e Jean-Luc Bertrand-Krajewski. "Neural networks for solid transport modelling in sewer systems during storm events". Water Science and Technology 33, n. 9 (1 aprile 1996): 85–92. http://dx.doi.org/10.2166/wst.1996.0183.

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Abstract (sommario):

Models for solid transport in sewers during storm events are increasingly used by engineers and operators to improve their systems and the quality of receiving waters. However, a major difficulty that prevents more general use of these models is their calibration, which requires field data, accurate information about catchments and sewers, and a specific methodology. Therefore, research has been carried out to assess the ability of connectionist models to reproduce and replace usual models for use by an operator. Such models require fewer data, are self-calibrated, and very easy to use. The first stage presented in this paper consists in a comparison between neural networks and the HYPOCRAS model, using simulations of real pollutographs for single storm events. Two specific recurrent neural networks based on the HYPOCRAS model and a general-purpose recurrent multilayer network are used to simulate hydrographs and pollutographs of TSS. The learning algorithm and the performance criterion used for optimization of these networks are described in detail. Experimental results with simulated and real data are then presented.

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46

Sawaki, Shimpei, Yuzo Tsuchiya, Takashi Yamauchi e Yuki Takenaka. "Experimental study on the sound of water flowing through a storm drain". INTER-NOISE and NOISE-CON Congress and Conference Proceedings 268, n. 2 (30 novembre 2023): 6477–87. http://dx.doi.org/10.3397/in_2023_0954.

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Abstract (sommario):

In buildings where storm drains are installed indoors, the sound of running water radiated from the surface of storm drains during rainfall may raise the noise level in rooms near the drain. To take appropriate measures against such sound according to the required quietness for the room, quantitative data on the sound of running water from storm drains is necessary, but few studies have dealt with this kind of sound. Therefore, the authors conducted experiments in an existing building, a drainage test tower, and a reverberation room to understand the characteristics of the sound produced by storm drains. Based on the results obtained through these experiments, this paper presents the effects of flow rate, pipe diameter, pipe material, and horizontal piping on the sound of running water from storm drains. The paper also discusses the differences between the sound generated by storm drains and the sound generated by sanitary sewers.

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47

Mikos, Éva. "Alligators in the Sewers". Ethnographica et Folkloristica Carpathica, n. 24 (5 settembre 2022): 7–29. http://dx.doi.org/10.47516/ethnographica/24/2022/10928.

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Abstract (sommario):

The aim of the present study is to provide an overall picture of the nature of urban folklore using the “Alligators in the Sewers” urban legend type circulated in both the Hungarian and international press and by word of mouth. While contemporary legends have attracted only sporadic attention in Hungarian research to date, by illustrating the historical development of this legend type the aim of the present case study is to demonstrate how the phenomenon has existed in the Hungarian press for almost 200 years. The present study attempts to identify the kind of opportunities for interpretation offered by these stories in the field of folkloristics; the extent to which they are relevant beyond their literal meaning; and the ways in which they shed light on modern-day understandings of the world. Giant reptiles that are not indigenous to Europe are terrifying to the average individual, while at the same time they evoke a yearning for the natural world in city dwellers trapped amid concrete walls. Urban sewers and storm drains hold similar terrors: on the one hand, they are there to remove filth and symbolize the more unsavory aspects of urban life, while on the other hand their hidden presence beneath the ground offers ample opportunity for the projection of numerous fantasies. Animals that lurk in the sewers, from where they emerge to attack people, are manifestations, contained within simple, traditional narrative frameworks, of the murkiness of highly structured societies and of the sense of danger that this opacity engenders in us. The emergence and persistence of such stories can be attributed to a number of social practices, such as circuses, sideshows, and the keeping of reptiles as pets, along with the respective press reports and rumors.

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48

Liu, Cuiyun, Wu Che e Ben Tan. "Determination of the Interception Volume of Storm Water Based on the Contaminants Transport in Storm Sewers". CLEAN - Soil, Air, Water 43, n. 11 (26 ottobre 2015): 1495–500. http://dx.doi.org/10.1002/clen.201300319.

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49

Trajkovic, B., M. Ivetic, F. Calomino e A. D'Ippolito. "Investigation of transition from free surface to pressurized flow in a circular pipe". Water Science and Technology 39, n. 9 (1 maggio 1999): 105–12. http://dx.doi.org/10.2166/wst.1999.0453.

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Abstract (sommario):

This paper deals with a phenomenon often occurring in sewers during storm events - transition from free surface to pressurized flow and vice versa. This transition is also possible in sewers where the discharge is controlled by some control devices, like gates. Experiments were carried out at a test rig consisting of a circular pipe with gates at the upstream and the downstream ends. Because of the relatively steep slope of the pipe and upstream boundary condition (flow below the gate), free surface flow at the upstream end was always supercritical, so that a hydraulic jump was always present during transitions (transcritical flow). Experimental results were used for verification of a numerical model based on a shock capturing method, the McCormack explicit finite difference scheme.

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50

Law, T. C., e Ian D. Moore. "Response of Repaired Sewers Under Earthloads". Transportation Research Record: Journal of the Transportation Research Board 1845, n. 1 (gennaio 2003): 173–81. http://dx.doi.org/10.3141/1845-19.

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Abstract (sommario):

The trenchless rehabilitation of damaged rigid sewers has become a competitive alternative to conventional methods of pipeline replacement. However, buckling caused by fluid load is identified as the important limit state in the current pipe-liner design standard, while the contribution of the damaged rigid host pipe in the assessment of resistance to earth loads as well as disturbance to the liner (e.g., vehicle loads) is neglected. Fullscale testing in the laboratory is used to investigate the soil–host and pipe–liner interaction. Two host-pipe–liner systems are examined. The first system involves a liner that fits perfectly inside a host pipe. The second system features initial lack of fit between the liner and the host pipe, and gaps across the fractures in the host pipe, to investigate ungrouted repair of rigid pipe with severe damage. The test geometry and measurement scheme to evaluate local bending and movement at the fractures in the host pipe are described. Key parameters affecting local bending are identified, including initial lack of fit between the liner and the host pipe as well as the hoop stiffness of the host pipe. This recent research on repair of sanitary and storm water sewers is discussed in the context of culvert rehabilitation.

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